I've acquired a Navigator 1 with my bike, but the backlight doesn't work correctly. I believe that this is the same as Streetpilot 3, is this the case? If so, am I correct to believe that the data cards are unique from other models and expensive to buy? I have 3 x 128mb data cards, I can't read them as my PC doesn't accept the reader software, probably due to me running Vista. I'm thinking of breaking the lot as I have the cards, the defective unit and a Touratech mount, plus cables and card reader etc. but I need to understand what I'm selling before I start.